Such pumps are known and are also designated as vane cell pumps in their construction. They are used for feeding gases or fluids and are used, e.g., in motor vehicles preferably as vacuum pumps for engine management and/or for boosting the braking force.
In DE 10 2006 058 978 A1, a pump (vane cell pump) is described in which a pump chamber comprises a pump ring that is arranged between a base plate and a cover plate. For reducing noise, a muffler is provided, but there is no front muffler. So that the gates are not tilted during operation and gate fractures are prevented, inlet openings are chamfered in the base plate.
DE 10 2009 056 010 A1 discloses a vane cell pump according to the class in which a front muffler is arranged in a muffler. An outlet opening of the front muffler has a cross section that tapers in the direction of the outlet. This prevents losses in power while simultaneously providing effective noise reduction.
From DE 42 39 575 C2, a muffler for vane cell pumps is known that is divided into two parts. One part is the suction side and the other part is the exhaust side of the pump. A filter sieve is arranged in the other part, in order to keep particles generated during production away from sensitive loads. A front muffler is not provided.
In the prior art it is not known to protect the sensitive pump itself from particles with filters, in order to guarantee the reliability and service life of the pump. It is only known to suction air from locations at which a particle load is relatively low. For this purpose, corresponding lines that reduce the pump output and increase the installation expense are required in vehicles.
Therefore the problem of the invention is to create a pump whose service life and reliability are improved with low installation expense in a vehicle. At the same time, the pump should have good sound damping.